Conventionally, there has been known a technology to recognize a face part imaged in image data such as a face-recognition technology.
Patent document 1 described below also discloses an apparatus recognizing the object in the image data and displaying information of an object together with the image data.
Meanwhile, a retrieval site on the Internet or the like provides an image retrieval service by performing a keyword retrieval of text information (image file name, shooting date-and-time information, etc.) accompanying the image data.    Patent Document 1: Japanese Unexamined Patent Application Publication No. 2000-113097.